1. Technical Field
This invention relates generally to take-up devices for electrical cords, and more particularly to those take-up devices for flat wire cables used in telephone communication and data transmissions.
2. Background
U.S. Pat. No. 5,230,481 (Wheeler et al.) discloses a dual reel cord take-up device for connecting a telephone and a cooperating handset. This device serves to connect the handset of a telephone to the body of the telephone with a device wherein the connecting cord is wound on a spool. This allows the user of the telephone to pick up the handset, move many feet away from the telephone, and still be connected by cable to the telephone body. Phone cable extends from both sides of the cord take-up device as the handset is moved away from the phone, and is wound back into both sides of the take-up device as the handset approaches the cradle. When the user returns the handset to the telephone, there is no pile of twisted and coiled extension cord. Instead, all of the phone cable is neatly wound back onto the dual-purpose shaft of the take-up device.
A feature of this system is that when the user of the handset returns the handset to its cradle, the dual-purpose shaft winds up the available cord. Just before the handset is placed on the cradle, the take-up reel, with its now much shortened external cable link, can contact the desk or table on which the telephone is situated. This contact can produce an audible clicking sound which the person on the other end of the telephone can hear.
There is a need to invent a device for feeding out electrical cable between a telephone and its handset, and for taking that cable up into a neat package, without having the take-up device be free floating between its attached ends, and without having the possibility of creating noise as the take-up device contacts objects during retraction and use.
What we have invented is a cord take-up device for flat wire phone cable which feeds out or takes up cable at only one of its two cable entry ports.
It includes a generally semi-cylindrical upper case half with two parallel compartments in a direction perpendicular to the axis of the cylinder, the first compartment being adapted to receive the first end of a dual-purpose dual-purpose  shaft, and the second compartment being adapted to receive the second end of the dual-purpose dual-purpose  shaft and a spring cup. The upper case half has snap-fit means for receiving a lower case half and means for receiving a flat wire cable.
Also provided is a generally semi-cylindrical lower case half, also with two compartments which correspond to the first and second compartments of the upper case half. The lower case half also has snap-fit means for receiving and cooperating with said upper case half snap-fit means. The lower case half has means for receiving a flat wire cable and has a second compartment with means for holding the spring cup in the second compartment against rotation in one direction but not the other.
Another feature of the invention is a dual-purpose shaft supported and held in rotatable relationship by both the upper and lower case halves. The dual-purpose shaft is provided on its first end in the first compartment of the upper and lower case halves with a slotted disk which divides the first end of the dual-purpose shaft into two adjacent chambers for receiving flat wire cable.
The flat wire cable extends through two apertures, with one cable end fixed in an aperture and the other cable end free to extend and retract through the other aperture.
The dual-purpose shaft has on its second end in the second compartment of the upper and lower case halves, a slot in the dual-purpose shaft for receiving a spring within the spring cup.
The device also contains a generally cylindrical spring cup within the second compartment of the upper and lower case halves, the spring cup having an outer surface perpendicular to its axis of rotation, means cooperating with the holding means to hold the cup against rotation relative to the upper and lower case halves in one direction but not in the other direction, and spring stop means on its inner cylindrical surface for foxing one end of the spring to the spring cup.
The device also contains a flat coil spring within the spring cup, the spring being fixed on its outer end to the spring cup and being fixed on its inner and end to the second end of the dual-purpose shaft.
Another feature of our invention is the inclusion of notches within the second compartment. These notches interact with the cooperating means of the spring cup, which are resilient prongs on its outer cylindrical surface.
Another feature of our invention is that the spring cup has detent means on its outer surface perpendicular to its axis of rotation for winding the spring.
Another feature of our invention is that the apertures in the lower case half are sufficiently large to permit the passage of flat wire cable in and out of the device, but are not large enough to permit the passage of a fold in the flat wire cable.
Another feature of our device is that the dual purpose shaft has a larger diameter in the cable extension and take-out reel than the diameter of the dual purpose shaft in the captive cable reel.
From the practice of our invention an improved phone cord take-up device is provided, wherein the device remains stationary in relationship to the telephone, and cable moves in and out of only one aperture of the device.